Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8353f940461e75f…

MALICIOUS

PDF

72.0 KB Created: 2021-09-19 21:26:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: dbe36d3c37741a1283a1d78b46d76d31 SHA-1: 34fe12030c5e6de94314389b4a653b0077f9811b SHA-256: d8353f940461e75f7f9f048d2eabcdf102f9a4a92abc0add47b54b231f7808fd
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high number of embedded URLs pointing to various domains, many of which are hosted on disposable or low-reputation sites. The ML classifier strongly indicated maliciousness, and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirms the nature of the links as a link farm. While no scripts were explicitly extracted, the presence of numerous external URIs suggests an attempt to redirect the user to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 4

  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crysiq.ru/uplcv?utm_term=how+to+download+minecraft+mobile PDF link annotation
    • http://theffirm.com/userfiles/file/88211225252.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/30600600431.pdfIn PDF document text
    • http://clearspace-design.com/CKEdit/upload/files/lenilurofemixili.pdfIn PDF document text
    • http://myphammonly.com/luutru/files/95842751748.pdfIn PDF document text
    • https://mjrspot.com/fckimages/file/59097057237.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/ditamukew.pdfIn PDF document text
    • http://sieuthibds.net/images/files/75004562635.pdfIn PDF document text
    • https://rgcsmt.org/ckfinder/userfiles/files/82473637744.pdfIn PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/91362264324.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/93663982378.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/21424766274.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/buxixawalilipot.pdfIn PDF document text
    • https://www.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/zajodejemefa.pdfIn PDF document text
    • http://myesen.life/userfiles/file/40506157607.pdfIn PDF document text
    • http://managhantasala.net/mailuserfiles/file/noxokabufejutalovuret.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/maxufan.pdfIn PDF document text
    • http://erdbau-rauch.at/9830777139.pdfIn PDF document text
    • https://okazionche.com/files/bikakobepokijaxitolifugom.pdfIn PDF document text
    • http://casavacanzesanvito.eu/userfiles/files/noxaj.pdfIn PDF document text
    • https://hattshopping.com/admin/assets/images/ckfiles/6683267748.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/68158778933.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161393b036d6d7---56125059430.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/53772794941.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133474692904---12098548523.pdfIn PDF document text
    • http://school15-tyumen.ru/f/razoliboradufexogulo.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b9b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C6 15864 bytes
SHA-256: 921bbe9dddd6656256a88fdc868639d297394d517a8fec38a101bb5852def231
font_02_sfnt_off0000fa0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0F 10684 bytes
SHA-256: a7573d78bd7261e006eaea6f49097410fc13b45d7b0b27d2fafe1d73c23d4905